This invention pertains to antennas to be used with an FM radio receiver. More particularly, the invention pertains to a high gain antenna with plural, mutually coupled conductive elements connected electrically in parallel which is particularly useful in areas where FM radio signals are weak and/or of distant origin.
Known antennas which have been developed for use in weak signal areas utilize a variety of structures to enhance reception of radio frequency (RF) energy. The most common structure used to enhance reception is a parasitic element. This element may be positioned adjacent, or several elements may surround, a primary conductive reception element.
Additionally, multiple conductive reception elements may be utilized, with or without associated parasitic elements, by coupling reception elements together, usually after such elements are positioned at varying heights, or with varying orientations, on a single antenna mast.
A third form of antenna utilizes an electrically conductive framework as a carrier for a conductive reception element which is electrically insulated from the framework but which is thought to derive some additional signal from the proximal association of the conductive framework.
Most known antennas require precise alignment with an FM transmission site in order to optimally receive signals from a specific site. This requires that antennas either be rotatably mounted, or be constantly adjusted for proper alignment. Additionally, the requirement for precise alignment makes the antennas particularly susceptible to variations in reception quality as a result of changes in atmospheric condition.
A general object of the instant invention is to provide a high gain RF antenna.
A further object of the invention is to provide an FM antenna which will provide parallel paths for RF energy.
Another object is to provide an FM antenna which does not require the use of parasitic elements.
A fourth object of the instant invention is to provide an FM antenna which will optimally function in a known frequency range.
Another object is to provide an FM antenna which is simple in construction and, therefore, inexpensive to manufacture.
A further object of the invention is to provide an FM antenna which does not need to be oriented in a specific direction to receive an RF signal from a specific transmitter.
The preferred embodiment of the instant invention includes a non-electrically conductive framework, which carries plural opened-loop, spaced-apart conductive reception elements. The conductive elements are electrically mutually coupled to one another intermediate the ends of the elements. An antenna lead is provided to connect the coupled elements to an FM radio receiver. The frame and conductive elements may be suitably enclosed in a supportable weather-tight container for suspension in outdoor conditions.
These and other objects and advantages of the antenna of my present invention will become more fully apparent as the description which now follows is read in conjunction with the attached drawings.